A study on the ongoing monitoring programmes in 13 European countries was made as part of a concerted action funded by the European Commission. Five main reference systems were used in the surveyed countries and three categories of bacteria were monitored, zoonotic agents, indicator bacteria and veterinary pathogens. The five reference systems and an overview of the national monitoring programmes are described. Differences exist and there is a real need for standardisation at the European level. This harmonisation could be set up both for microbiological methods and the epidemiological results derived from common methods. Disk diffusion methods are most widely used and many of the monitored species and control strains are similar in the action's participating countries.